Resources

General Management

• CropManage - A comprehensive irrigation and nutrient management decision support tool that utilizes CIMIS and UC research to calculate crop-specific fertilizer and irrigation needs. For guidelines and updates, visit the CropManage Blog. (UC ANR; Michael Cahn)

• Nitrogen management training modules for Certified Crop Advisors - Collection of learning modules created with support from the California Department of Food and Agriculture in order to help growers develop efficient nitrogen management practices.The training was offered to Certified Crop Advisors (CCA) around the state. (UC ANR)

• What's in your nitrogen budget? - Summary of the key components of a nitrogen budget. (Robert Mikkelsen, International Plant Nutrition Institute)

• Nitrogen management plan worksheet instructions - Sample nitrogen management plan worksheet annotated with descriptions of each section and recommendations of data sources that can help with the calculations of each section. (Central Valley Regional Water Quality Control Board

• Approved farm evaluation plans for growers - Approved farm evaluation plans, nitrogen management plans, and more from the 14 water quality coalitions in California. Also includes a map of the water coalition boundaries and forms to join a coalition group. (Irrigated Lands Regulatory Program)

• The California Nitrogen Assessment: Challenges and Solutions for People, Agriculture, and the Environment – The first comprehensive account of nitrogen flows, practices, and policies for California, encompassing all nitrogen flows—not just those associated with agriculture—and their impacts on ecosystem services and human wellbeing.

• Russell Ranch Agroecological Research – At Russell Ranch, long-term monitoring and experimentation assess the sustainability of agricultural production. Faculty and researchers to conduct a variety of experiments with access to a wide collection of supporting data. Data collection includes water and fertilizer inputs, yield, weather events, pest pressure, soil microbiology, energy use, and more.

• FREP Database (CDFA) - A searchable database of all FREP (Fertilizer Research and Education Program) funded research. The database is searchable by crop, county and date range, and results are in the form of concise summaries with links to the full research report.

• Fertilization guidelines for major crops grown in California (CDFA) - A growing resource fertilizer guidelines for 16 major crops describing nitrogen, phosphorus, potassium and other important nutrient guidelines.  Information on soil tests and leaf analysis is also provided.

• Nutrient management resources (Daniel Geisseler, UC Davis and Asif Maan) - A selection of online resources, experts, electronic Journals and books focused mainly on nutrient management in California agriculture.

• International Plant Nutrition Institute Tool Box (IPNI) - A selection of calculators and tools that provide estimates for crop nutrient removal, response, trends in soil test results, yield loss from nutrient rate reductions, and more. 

Testing

• Soil sampling instructions
  (UC Davis in collaboration with Fertilizer Research and Education Program)

• Soil Sampling Video Series
  (Fruit & Nut Research & Information, UC Davis)

• Details on nitrate quick test
  (UC Cooperative Extension - Richard Smith)

• Economic benefit of pre-sidedress soil nitrate testing
  (Natural Resource Conservation Service)

• Guide to nitrogen test for vegetables with the ‘Cardy’ Nitrate meter 
  (UC Cooperative Extension - Kurt Schulbach, Richard Smith, Tim Hartz, Louise Jackson)

Nutrient budgeting

• Crop nutrient harvest removal - Discusses considerations in calculating nutrient concentrations, including adjusting for different moisture contents. Provides a table of typical yields and nutrient concentrations for common grain/forage crops. (UC Manure Technical Guide Series)

• Crop uptake and partitioning - A generalized pattern of seasonal N uptake for several commonly grown crops. Includes results of research on nitrogen partitioning and the amount of N removed at harvest. (UC Davis in collaboration with Fertilizer Research and Education Program)

• Manure nitrogen mineralization - An overview of the basics of N mineralization from manure, reasons for variability in manure N content, mineralization rates and considerations in predicting N availability from manure over time. Provides calculations to estimate plant-available nitrogen for animal manures. (UC Cooperative Extension Manure Technical Bulletin Series)

• Estimating nitrogen for organic crop production (worksheet and guide) - Information and worksheet to develop a complete nitrogen budget, or for estimating and understanding plant availability of nitrogen from individual organic nitrogen sources, such as compost or cover crops.

• Nitrogen in organic matter and mineralization rates - Includes specific information on mineralization rates of organic matter, crop available N from legume cover crops, crop residues, alfalfa, manure and more. (UC Davis in collaboration with Fertilizer Research and Education Program)

• Nut orchard nitrogen calculator - Calculates nitrogen fertilizer recommendations accounting for N credits including irrigation water, cover crops, compost and other sources. Must create an account with almondstewardship.org to access. (Almond Board of California)

• Nitrogen Budgeting Worksheet for Walnuts - Calculates an N budget accounting for past yield data, irrigation records, nitrate in irrigation water, compost, and manure applications as well as cover crops. (UC Agriculture and Natural Resources; Kathy Kelley and Joe Grant)

Irrigation Management

• CIMIS irrigation scheduling - Online resources for scheduling irrigation using Evapotranspiration data from the California Irrigation management Information System (CIMIS). (Center for Irrigation Technology at California State University, Fresno)

• Domestic and Irrigation Well Monitoring and Reporting Guidance -This protocol it provides a good framework for the sampling of irrigation water in general. (California Water Boards Central Coast)

• Evaluating water quality - A guide for self-assessment techniques for evaluating water quality. Covers several parameters of water quality including a section on testing for nitrate. (UC ANR)

Fertilizer Management

• Published UC nitrogen fertilizer rate guidelines for select crops - Table from Nitrogen fertilizer use in California: Assessing the data, trends and a way forward, published in California Agriculture. (Rosenstock et al. 2013)

• California Fertilization Guidelines for Major Crops - Fertilizer Guidelines for main field and tree crops grown in California, based on research carried out in California and elsewhere. (UC Davis in collaboration with Fertilizer Research and Education Program)

• Nutrient Source Specifics (Fertilizer fact sheets) - Fact sheets on the specifics of commonly used fertilizers and nutrient sources. (International Plant Nutrition Institute)

• Nitrogen management training videos (UC ANR California Institute for Water Resources)- Presentations and videos on California's nutrient management regulations, nitrogen basics, irrigation and fertilizer management. 

• Nitrogen prediction models for almond and pistachio (UC Davis) - A selection of tools for managing and predicting nitrogen in almond and pistachio. Includes a model that calculates N budget based on projected yield and guidelines for early season sampling and in-season budgeting.

• Nitrate to nitrogen conversion and estimating N contribution from irrigation waters containing nitrate (UC ANR) - A blog post that provides a useful set of conversion rates to convert between nitrate and nitrate-nitrogen, as well as ppm nitrate to pounds N/acre inch and pounds N/acre foot. The post also discusses considerations in determining how much nitrogen in water should be credited to your crop.

Cover Crops

• SAREP cover crops database (UC SAREP) - A database of common cover crops used in California agriculture.  Entries include information on cultivar, management, potential tradeoffs and benefits of use.

• Selecting the right cover crops gives multiple benefits (California Agriculture) - An article discussing the benefits and tradeoffs of common California cover crops. Includes information on water use, pest management, growth habit, and incorporation of cover crop in rotation.

• Cover Crop in Organic Systems, a California Implementation Guide (NRCS, NCAT, Xerces Society) - A detailed, California specific resource explaining the use of cover crops in organic systems.

• Cover crop economics tool (USDA) - A user-friendly economic assessment tool to assess the costs and benefits of incorporating cover crops into a crop rotation.  The tool assesses both he short term and long term expected costs and benefits.

• Entries on cover crops in the Solution Center Database

Videos discussing cover crops

• Are legume-cereal cover crop mixtures a good fit for organic vegetable production?(USDA-ARS) A video from Eric Brennan discussing the pro's and con's of using legume-cereal cover crop mixtures in organic vegetable production.  Based on data from short and long-term research in vegetable production zones, mostly in the central coast region of California. 

• Who's Your Farmer California? Cover Cropping with Martin Burger  (Sustainable World, UC Davis) UC Davis researcher Martin Burger discusses the use of cover crops on the Russell Ranch Sustainable Agriculture Facility

• Cover Crops and Water Infiltration of Soil (NRCS California) Russ Lester, a walnut grower in Winters, California, discusses a cover crop he seeded with support from the EQIP program.  He focuses specifically on the benefits of cover crop for increased water infiltration

Soil Organic Matter

• What does organic matter do in soil? (The Samuel Roberts Noble Foundation) - The basics of soil organic matter (SOM), it's role in soil and a list of management practices that could increase SOM.

• Soil fertility in organic systems: lessons from long-term studies (UC Davis) - Presentation of results of long-term research in california, focusing on managing soil fertility in organic systems, including the role of soil organic matter.

Agriculture, Nutrient Management and Climate Change

• Climate Solutions in California Agriculture (California Climate and Agriculture Network) - A summary of the organic and sustainable farming and ranching practices that could provide climate benefit from the California Climate and Agriculture Network.

• What Does California Climate Legislation Have to Do with Agriculture? (California Climate and Agriculture Network) - A breakdown of California's landmark climate bill AB 32 and how it may impact farmers and ranchers.

• Sources of Greenhouse Gas Emissions: Agriculture (US EPA)- A summary of the greenhouse gas emissions and trends from agricultural production, and some strategies for reducing emissions from agriculture

• The California Air Resources Board Greenhouse Gas Emission Inventory Query Tool (CARB) - This tool allows you to select from major economic sectors, and greenhouse gases that you are interested in. 

• Entries on nutrient management and greenhouse gas emissions in the Solution Center Database

Videos on agriculture, nutrient management and greenhouse gas emissions

• Greenhouse gases associated with agriculture (Livestock & Poultry Environmental Learning Center) An explanation of the greenhouse gases that are emitted from agricultural management. Includes a discussion on the importance of nitrous oxide and methane emissions.

• Denitrification (Sciencelearn.org.nz) This video from New Zealand explains the process of denitrification, where soil microbes convert nitrate into nitrous oxide, a potent greenhouse gas.  Although not specific to California, the basics of denitrification and conditions under which it occurs are explained well.

• Soil building for climate resilience webinar (California Climate and Agriculture Network) The benefits of building healthier functioning soils that can help growers cope with a changing climate while potentially mitigating agriculture's contribution to climate change are discussed.  Speakers include Rex Dufour (ATTRA/NCAT), Jeff Creque (Marin Carbon Project, and Jocelyn Gretz (Rio Farms).